magazinesfromthepastfandomcom-20200214-history
PETChess
Reviews Summary Your Computer Issue 8 Writer: John White PetChess was written by Philidor Software especially for ACT/Microsoft for the Pet 3000, 4000 and 8000 series. My review tape occupied almost the entire memory of a 32K 8032 Pet and, for the first time, I realised the privations of those who have to load tapes at 300 baud, although a disc version is also available. PetChess is claimed to offer more facilities than any other chess software. Setting up positions is exceptionally easy and so is retracing moves. There is, however, no hint button to tell you what to do on your move. An audio alert is also available for the 8000 series. There are 12 levels of play from five seconds to 40 minutes. The graphics are very easy to understand — by way of a change — and the program seems to be crashproof. There is a substantial book-opening library of 3,700 moves, although whether a computer should play the dubious von Hennig-Schara gambit is open to doubt. Moves may be taken back to the beginning and an action replay is available to repeat moves. The program uses iterative deepening for its moves and the best move yet found is constantly displayed, as is the move under consideration, and the player can halt the machine's thinking at any time. Moves are not randomly selected — except in the opening — instead the player can select the next best move and play on from there. Draws under the 50-move rule, stalemate or three-fold repetition are also recognised. The entire program and its style of play is reminiscent of Philidor's Intelligent Chess, although there is a greater emphasis on pawn moves. The evaluation function is evidently very sophisticated, but it takes a long time to search at the lowest levels. It seems that subsequent levels arc only sketchily evaluated, and the program rarely changes its mind about a move found at the lowest level. As a result, PetChess falls into simple traps at these levels — up to one minute, which covers half of the available levels — because of its inability to see far ahead. At higher levels, it avoids the traps, but tends to exchange everything it can. Like so many programs, it likes to exchange its bishops for knights early in the game, and it also prefers to double its pawns rather than move its queen before castling — I detect Levy's hand. PetChess shows some evidence of strategic thinking in moving pawn majorities against minorities or in moving major pieces into attack positions against the enemy king. This, again, shows the thought that has been put into the evaluation function. The end-game play is, however, rather weak, and the king seems to be a little passive. PetChess is not as strong as the Sargon II cassette program, which in any case is not available for the Pet in this country. PetChess is certainly the strongest chess program for the Pet available in the U.K. and is good value at £25. Despite my criticisms, I gained a great deal of enjoyment from PetChess and can recommend it to Pet chess players of club standard. Category:PET Games Category:Philidor Software Category:Your Computer Reviews